以下代碼是用物體框架6和物體框架加庫（期貨）撰寫的
using (var ctx = _contextCreator.PortalContext())
{
var q = "";
ctx.Database.Log = s => q =s;
var a = ctx.ArticleIcons.Take(1).Future();
var b = ctx.ArticleIcons.Take(3).Future();
var aResult = a.ToList();
}
這是“q”變數的輸出，用于輸出生成的 SQL 查詢。是否可以避免執行 4 個查詢，因為代碼中只有 2 個查詢？
SELECT TOP (1)
[c].[Id] AS [Id],
[c].[Name] AS [Name],
[c].[CssClass] AS [CssClass]
FROM [dbo].[ArticleIcons] AS [c]
-- Executing at 25.3.2022. 9:41:47 01:00
-- Completed in 29 ms with result: null
SELECT TOP (3)
[c].[Id] AS [Id],
[c].[Name] AS [Name],
[c].[CssClass] AS [CssClass]
FROM [dbo].[ArticleIcons] AS [c]
-- Executing at 25.3.2022. 9:41:47 01:00
-- Completed in 0 ms with result: null
Opened connection at 25.3.2022. 9:41:48 01:00
-- EF Query Future: 1 of 2
SELECT TOP (1)
[c].[Id] AS [Id],
[c].[Name] AS [Name],
[c].[CssClass] AS [CssClass]
FROM [dbo].[ArticleIcons] AS [c]
;
-- EF Query Future: 2 of 2
SELECT TOP (3)
[c].[Id] AS [Id],
[c].[Name] AS [Name],
[c].[CssClass] AS [CssClass]
FROM [dbo].[ArticleIcons] AS [c]
;
-- Executing at 25.3.2022. 9:41:48 01:00
-- Completed in 53 ms with result: SqlDataReader
Closed connection at 25.3.2022. 9:41:48 01:00
uj5u.com熱心網友回復：
由于以下原因，查詢被記錄了 2 次：
第一次，庫生成兩個查詢（不執行它們，只生成它們）。但是，要正確生成它，它必須呼叫記錄這兩個查詢的攔截器ReaderExecuting 和 ReaderExecuting。此步驟是強制性的，某些提供程式（例如MySql/custom 用戶代碼）更改查詢和引數。
第二次，組合查詢后，庫呼叫DbInterception.Dispatch.Command.Reader攔截器，該攔截器記錄組合查詢。
因此，雖然查詢由于限制已被記錄了 2 次，但在資料庫服務器中只執行了組合查詢。
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